Process for the production of unsintered binding means of oil shale and limestone and the like



Patented Apr. 10, 1928. 3

UNITED STATES 1,665,993 PATENT OFFICE.

oscAR 'rn'rnns, or OERLINGHAUSEN LIBPE, GERMANY.

raocnss ron'rnn raonucrroiv or onsm'rnann BINDING MEANS or on. SHALE Ann LIMESTONE? AND THE LIKE.

No Drawing. Original application filed January Filed in Germany May 21, 1922. Divided and 758,774.

The technical exploitation of the oil-shale has given certain practical results especially at the present time. 'Oil-shaleis for instance utilized in such a manner thatthe 5 residue of its gasification is Worked up to artificial light stones. It has also been proposedto produce, by burning, cement, a

sinter product, from the shale or fromthe residues after admixing the same with ground lime. 4

This invention relates also to this problem. When getting distillation products from shale and the burning of an unsintered hydraulic binding material is carried out simultaneously in the samefoperation, the

heat produced by the combustion of the organic constituents of the shale, which have not been separated by distillation, is utilized to burn coke, lime-stone, chalky marl or the like which have been charged together with the raw shale. It has already been proposed to admix with the shale to be gasified small quantities of lime and chalky marl in order to be able to make after the burning of the shale ash building stones directly from the burnt material, the additions were however infinitesimallysmall while, according to my invention, they amount to 3550% of the total charge and, if suitable chalky marl is used as addition, to an even higher ercentage.

Ithas hitherto been believed that the calcining of lime-stone and the like by means of oil-shale were possible only with the aid of auxiliary fuel or with great quantities of shale. For this reason it is, according to another process of burning lime stone by means of oil-shale as a source of heat energy, necessary that the lime stonebe charged into the kiln separately from the oil shale, that is traverses the kiln separately and is discharged from the kiln separately.

It has been discovered that these special measures are quite unnecessary and not only when oil-shale is used which possesses for instance a ealorimetric value of from 2500 to 3500 calories, but even when oil shale is used the ealorimetric value of which amounts to 800 to 1600 calories.

According to my invention the hot gases from combustion drive out the substances which are capable of being distilled out of the shale as it passes through the oven and 26, 1924, Serial 110., 688,831. Patent No.'1,586,165.

this application filednecember 29, 1924. Serial m.

which they encounter above'or beyond the.

combustion zone proper. The air required for the combustion flows, before itfcomes to combustion zone, through the hot zone of thoroughly burnt mixture. This air becomes heated by the residues and cools them according to the counter-current principle, so that the loss'of heat is very low.

The practically complete combustion of the carbon of the shale-coke to carbon oxide is ensured, notwithstanding the" high stock column used in the interset of the completest possible distillation of the volatile constituents of the oil-shale. The added lime-stone or calcareous marl acts upon decomposition by the heat, as heat absorbing material, preventing thus the formation of a too high temperature which would cause a decomposition of the carbon dioxide produced and therefore be unfavorable for the thorough combustion of the carbon to carbonic acid,

If the oven or shaft kiln is well insulated against the ambient air almost the total heat gibegated from the shale coke can be utiize As the shale residues, as lime and aluminium silicate-containing materials, are opened at the burning they are capable of forming a valuable hydraulic binding material if ground with chalky lime or chalky marl or the like.

The process according to my invention can be applied also if lime-stone and shale are ground prior to the burning process and subsequently moulded to lumps.

VVhen' working according to the methods explained it is also possible to work in a part of the kilns onshale-lime or on Roman cement, as much lime-stone or chalky marl being charged as possible (.for one part of shale up to 7 parts of the lime-containing substance according to the quality of the shale and to the composition of the limestone or the chalky marl). .In the other part of the kilns the shale can be gasified in the commonly used manner without addition of lime. The gases produced can be used for I instance for generating the energy required for the grinding of the binding material, the shale residue -from this kiln being admixed with that from the other kilns, which is comparatively rich in lime, to be ground together wi h the same, the binding material would otherwise be.

The process can be carried out in the shaftkiln as well as in the revolvin tubular kiln.

When shaleand lime-containing substances have hitherto been used to make binding material the purpose was to produce products similar to Portland cement or sintered prod: ucts, the lime-containing substances Were added only in limited. quantity. The lime containing material was added only after the shale was distilled. In opposition hereto the shale is burnt, according to my invention, with a very high addition of lime and worked in order to obtain an unsintered product.

I claim. v I

1. A process forthe production of a hydraulic binding material from oil-shale and lime-containing material, which comprises mixing the raw shale with lime-containing material capable of being calcined by the shale, distilling themixture and recovering distillation products from the oil shale and burning the mixture'by the shale-coke obtained from such distillation in the same kiln and grinding the residues obtained by such burnings 2. Aprocess for the production of a hydraulic binding material from oil-shale and lime-containing material, which comprises grinding the raw shale together with at'least thi lzy-five percent: of lime-containing mater distillin the mixture and recovering distillation proc lucts from the oilshale, burningnthe mixture without sintering in the same ki only by the shale coke distillation resimemes due, and grinding (the residuesobtained by such burning. 4

3. A process for the production of a hydraulic binding material from oil-shale and lime-containing material, [which comprises grinding the raw shale together with at least thirty-five per cent of lime containing material, molding the ground material to lumps; distilling thelumps and recovering distillation products from the oil-shale, burning the mixture without sintering by the residual shale-coke in the same kiln and grinding the residue obtained by such burning.

4. A process for the roduction of a hydraulic binding material lime containing material, which comprises from oil-shale and.

charging into one of a group of kilns raw shale mixed with a highest possible amount of lime-containing material capable of being calcined by the shale, distilling the mixture in a kiln and recovering distillation products.

from 'the oil-shale, burning the mixture in the same kiln Without sintering by the shale coke remaining from the distillation and distilling in another kilnthe raw shale without addition of lime-containing material, and grinding the residues from both kilns together to form hydraulic binding material.

5. The method of producing an unsintered hydraulic binding material which comprises mixing raw oil shale with at leastthirty five percent calcareous material, distilling the mixture and simultaneously caecining the material by the shale coke in the same kiln.

In testimony that I claim the foregoing as'my invention, 1 have signed my name.

' OSCAR TETENS. 

